Electronic ballasts are subject to many safety standards, including the capability of preventing from electric shock through lamp leakage current. In order to reduce the risk of electric shock during re-lamping, a ballast is typically required to comply with the safety standard recited in UL 935 section 24. This standard requires ballast operation to cease if a lamp leakage fault is detected and leakage current is more than a prescribed limit. Typically, operation of the ballast is ceased by discontinuing the operation of the inverter circuit within the ballast.
Some ballasts include an inverter that continues to attempt to restart a lamp after occurrence of a fault, to avoid having to toggle input power to the ballast in order to ignite the lamp. One such example is a ballast available from OSRAM SYLVANIA Inc. of Danvers, Mass., which use an integrated circuit from Infineon Technologies. This feature helps in cases of false detection of a fault, and in cases where a ballast initially fails to ignite the lamp(s) to which it is connected.